Symptoms of rice brown blight

Rice red blight, also known as iron rust, is a common physiological disease in rice cultivation. The occurrence of this disease is easy to reduce the yield of rice. What are the symptoms of rice red blight? How to prevent and cure it?

1. Symptoms of rice red blight

1. Cold injury type: it mostly occurs in mud field, deep foot field, cold soaking field and back shade field, which is caused by low soil temperature or early planting. After planting, the roots are aging, brown and soft, the roots are few and thin, the vitality is blocked, the growth is slow, the leaves are erect, there are irregular brown spots near the tip, and gradually spread to the base along the edge, the foot leaves turn yellow, and the plant shape is small.

2. Element deficiency type: due to the lack of nutrient elements, the lack of elements hinders the physiological metabolism of seedlings. In the fields deficient in phosphorus, the new roots of the seedlings are few, the roots are brown and black, the seedlings are brush-shaped, and the leaves are dark brown; in the fields lacking potassium, the roots grow weakly, the leaves are short and dark green, there are reddish brown spots on the old leaves, the leaves are easy to break, and the veins of the main leaves are yellow; in the fields lacking zinc, the heart leaves of the seedlings are curled and not easy to be extracted, the leaves appear green stripes in the seedling stage, the roots are short and few, the leaves are white, and the leaves are arranged in palms.

3. Poisoning type: it mostly occurs in long-term flooded deep foot fields, soil permeability poor flushing fields, rotten mud fields, large fertile fields in front and back of houses, and so on. The seedling yellowed and did not turn green, the root brown gradually turned yellow, the soft cotton shrunk, the old leaves yellowed, and there were reddish-brown spots on the leaves. In severe cases, the lower leaves of the whole plant turned red, occurred in pieces or clumps, and the seedlings were upright.

2. How to control rice red blight

(1) improve the soil, deepen the tillage layer, increase the application of organic fertilizer, improve the soil fertility and improve the soil aggregate structure.

(2) potassium fertilizer should be applied early, such as potassium chloride, potassium sulfate, plant ash, potassium calcium fertilizer and so on. Phosphorus-deficient soil should be early applied, concentrated application of calcium superphosphate 30kg per mu or spraying 0.3% potassium dihydrogen phosphate aqueous solution. Do not apply nitrogen fertilizer alone, otherwise the disease will be aggravated.

(3) transform low-lying flooded paddy fields and make drainage ditches. Green manure should not be used as base fertilizer, and ploughing should not be too late. The application of organic fertilizer must be rotten and applied evenly.

(4) early rice should be irrigated frequently and cultivated in time to increase soil permeability.

(5) the diseased rice field should be drained immediately, lime should be applied, and the field should be shelved slightly to promote the settling of floating mud so as to benefit the early development of new roots.

(6) 500-600 times of Wanjiabao, a multi-functional and efficient liquid fertilizer, was sprayed on the leaves of rice from booting stage to filling stage, once every 15 days.

(7) the prevention and control of cold injury can cultivate strong seedlings mainly raised by drought, and enhance the cold resistance; semi-dry cultivation is adopted in rotten mud field, deep foot field and cold soaking field to increase soil temperature; ditch to draw cold water; shallow irrigation, drainage and drying field, increasing temperature and aeration to reduce toxicity.

(8) the prevention and control of poisoning can adopt semi-arid cultivation, improve soil ventilation, reduce the reduction of toxic substances, apply more organic fertilizer, not immature organic fertilizer, green manure should be buried early and let it decompose and mature, drainage and sun-drying field, increase temperature and ventilation; apply lime to neutralize poison, increase phosphorus, potash fertilizer and ash fertilizer to enhance stress resistance; shallow water irrigation.

This is the end of the brief introduction of rice red blight. Friends in need can learn about it. I hope it will be of some help to you.